In the past I’ve published articles on how to do a benchmark with namebench to see what’s the fastest DNS server for you and how to crypt your DNS traffic if you use Opendns but I’ve never done a comprehensive guide of the command dig, probably the best command you can have on the command line to query a DNS server, so today I want to show you the basic usage of this command and some trick, using examples that you can re-use for your goals.
But as first thing, probably every reader know what’s a DNS server, but anyway it’s better to take the good definition from Wikipedia:
The Domain Name System (DNS) is a hierarchical distributed naming system for computers, services, or any resource connected to the Internet or a private network. It associates various information with domain names assigned to each of the participating entities. A Domain Name Service resolves queries for these names into IP addresses for the purpose of locating computer services and devices worldwide.
So let’s see how we can query a DNS server o get all the info we need.
